The former Barca coach kept a low profile in the stands and would have been very happy with the outcome of the match as the Catalan giants took a comfortable lead in the two-legged tie.
Liverpool were at times dominant in the match but will be ruing a number of crucial missed chances after Luis Suarez opened the scoring and Lionel Messi followed up with a brace late in the second half.
Jurgen Klopp’s team will need a monumental effort in the second leg at Anfield to have any chance of progressing to the Champions League final.
Guardiola’s City are currently locked in an extremely tight battle for top spot with the Reds and will be hoping for similar results from his domestic rivals' last two Premier League matches of the season.
With Liverpool just a point behind City in the league standings, neither team can afford a dip in form if they want to secure the prestigious title.
The Reds will be looking to bounce back from their disappointing midweek loss when they visit Newcastle United on Sunday, while City host Leicester on Tuesday.
